This R01 proposal focuses on a new emerging disease, Nephrogenic Systemic Fibrosis (NSF), which affects patients with severe renal impairment. NSF is a progressive, debilitating disease with increased morbidity and mortality and has been linked to exposure to gadolinium (Gd) based contrast agents used in Magnetic Resonance Imaging (MRI). The 2007 FDA's box warning regarding the risk of all gadolinium-based contrast agents in developing NSF may affect a large number of patients (e.g., an estimated 27.5 million MRI procedures were performed in 2007 in the U.S. alone and 43 percent used Gd based contrast agents as part of the imaging procedure). At present, radiologists are hesitant to administer any type of Gd based contrast agents to patients with any level of renal impairment, which makes it difficult for clinicians to obtain high resolution imaging for patients with renal insufficiency. Few studies have relied on animal models to study how Gd based contrast agents trigger NSF, but rats with normal kidney function used in the studies fail to represent patients with renal failure, a pre-existing condition for most NSF cases. Currently, there is no effective treatment for NSF, thus the only recommended action is hemodialysis to remove the Gd contrast agent from the blood. However, proof of hemodialysis efficacy is lacking. Our proposed work is innovative because it will utilize a chronic renal failure (CRF) rat model to study NSF that is triggered by Gd based contrast agents, followed by applying our new decorporation method based on advanced functional materials to remove the Gd contrast agent from the animals. Specifically, once the chronic renal failure (CRF) rat model is produced by adenine dosing, NSF disease in these animals will be studied as a function of dose-dependency and chemical structures of Gd based contrast agents as well as involvement of other indigenous metals. Pharmacokinetics of the Gd based contrast agent will be studied in order to optimize the removal strategies by both novel decorporation and hemodialysis methods. The efficacy of both methods will be assessed in terms of the reduction of blood and tissue Gd content and the prevention of NSF incidence in the animals. This research is directly responsive to PA-08-251: Metals in Medicine, since it involves the interactions of synthetic inorganic complexes with living systems and their components as well as diagnostic and therapeutic applications of metal complexes and of metal chelators. Through the collaboration among leading inorganic chemists, physicist, and toxicologist at the Pacific Northwest National Laboratory (PNNL) and experts in dermatopathology and nephrology at the Oregon Health & Science University (OHSU), our research team is uniquely capable of studying both NSF mechanism and prevention approaches. The propose work also aligns well with the mission of National Institute of General Medical Sciences (NIGMS), which is Supporting research that is the foundation for disease diagnosis, treatment, and prevention.